New details are emerging about how the shadowy data firm Cambridge Analytica worked to manipulate voters across the globe, from the 2016 election in the United States to the Brexit campaign in Britain and elections in over 60 other countries, including Malaysia, Kenya and Brazil.

This chilling documentary lays bare the cynicism and chaos surrounding the data research company that harvested information from millions of Facebook users.

Legal threat comes as campaigners warn UK government that courts are being used to intimidate journalists.